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Yep I have cut 3 1/2" holes in 1/2" plate using a hole saw with my drill press.
But even using a hand drill ,speed and feed. I use a hand drill for tapping holes also, 4-40 to 1/2 inch. Too lazy for hand tap wrench.

hand drill tapping

Originally Posted by tnjind

I use a hand drill for tapping holes also, 4-40 to 1/2 inch. Too lazy for hand tap wrench.

Wow, that sounds pretty bold. I imagine you broke a few trying to get the feel of it. Or, maybe you have very high quality taps. I recently did 16 3/8 in. holes for a set of casters. That did get old. I was really afraid I might break my cheap Lowes tap even doing it by hand.

Been doing this for a few years, I did break a few, its all in the feel. I use cordless drills, 18volt or bigger. I have Porter Cable 19.2 that is a real workhorse. I am on the second chuck, I use channel locks to tighten it with 1/2 taps.

I've got a couple of sets of older Craftsman HSS bits up to 1/2" that have been decent to me. I've got other various ones up to 1". I do keep them sharp and don't burn them up with speed. Keeping a bit sharp is the key to success. No cutting tool works very good when dull. Sharpening a bit isn't difficult if you own a bench grinder with a fairly fine wheel on it. I use the side of the wheel and duplicate the angle of a new bit. If you don't know what that is, go get a new bit and hold it against the wheel to get the idea. Use water and don't burn the bit up on the grinder! If you keep them fairly sharp it doesn't take much to touch them up and keep them like new.

I have two sets of Chinese made Zirconium Nitride bit sets one I bought about 3 years ago at Costco. I think it has Master Grip printed on the front and another I just recently purchased at HF. Both sold for around $50.00us and appear to be the same bits. They have approximately 100 bits in fractions, wire gauge and letter gauge. Very handy for matching taps with drills. The Master grip set has been very durable and the bits stay sharp for a long time. I drilled 112, ¼” holes in 1X2” steel bar for a shelf pin hole guide. I also have a Dewalt set that has not been as durable as the Chinese made drills. The Chinese drills are all different lengths, if you compare different sets next to each other the drills of the same size will often be different lengths. I believe these sets are made up of industrial drills that have been re-sharpened and re-coated. Not sure but it makes sense to me and would explain the high quality steel at such a low price. As said above speed is very important, slower for larger dia and faster for smaller. Plenty of coolant/lube for steel. Aluminum is not a coolant critical as long as the bit is sharp and cutting in new material each revolution.

well for the bits i buy viking tools bits but once again have to keep sharp and use the right pressure. as for cutting oil i use rapid tap for general holes but it does not weld well. water soluble oil that u use in ur band saw for holes that get welded that cant get a clean up, but my trick for lots of holes in thick material i use kerosene. yes it does work freaking awesome its a old millwright trick. one 1/2 in drill bit drilling 2.5" thick material lasted 35 holes not bad for a $30 bit.

i think the chinese bits in the huge sets are very brittle. they cut well and last long but i did hang one up (3/8") and one side of the tip snapped clean off.

i have several sets of bits but my go to set is an irwin from costco and they have lasted very long with care. for steel, slow speed and high pressure. if you getting curlies and there not blue your doing well.

At work they used to order two types of drill bits (don't ask why... ), some were cheap junk and the others were TiNi coated Norseman bits. The Cheapies usually lasted about 10 holes with a hand drill and that was about it. The Norseman's would go for a very long time as long as you didn't do anything stupid, but the do cost a lot more.

Bit speed is crucial to making fast, efficient cuts and helping extend the life of the drill bit. I recomend finding a speed chart from a manufacture or reputable source, just remember slower is not always better. Running a 1/4" drill bit on the slowest speed only prolongs the agony of drilling the whole and wears the bit out faster.

homier drills

this bit is from an outfit that shows up in town every now and then and sets up for a few days and sells tools and whatever. This bit was used to drill holes in wood for picnic table seats. The guy hit a steel brace on the other side of the wood. He was using this in a battery operated drill. When I saw it I thought it was some specialty drill. Silly me.